Hi,

We've had this upright freezer for at least 30 years now and have never had a problem with it. A few weeks ago, however, I noticed that there was some type of liquid that seemed to be coming from the unit. I checked inside and indeed some stuff had begun to defrost. I unplugged the unit and let it defrost. I then plugged it back in. It was working well for about a week then decided to stop staying cold, again. I haven't been able to find any manuals for this model because it is so old but want to fix it because it has been a great unit and deserves to stick around.

What sort of tests can I do that will enable me to determine the fault of this malfunction?

All of the specs for this unit are as follows:

Westinghouse
S/N: 709186
Model: UFE120
Style: 045182
Model Unit: N U12